The implication is that mechanical vibration induced by the sound pressure waves in the room provide the mechanical excitation (work).jneutron said:
For home stereo at an SPL of 90 dB, implies a human hearing range of 10^9 or 100 million to 1 (in an utterly quiet room).
So John, math and physics being very much up your alley;
Let's assume the speaker cable is charged to an instantaneous level of say 10 Volts (that's about 12 watts) and the wires move say 0.5 millimeters due to acoustic vibration. Let's also say the distance over which the wires are disturbed runs about 1 meter or more simply say 100 pF, how much power is induced into an 8 Ohm load?
I think we're all on the same page as what we're questioning is the audibility of such artifacts at conventional amplification levels.
And of course whether it's worth paying £6000 - £12000 ukp to be rid of them.
regards
Raja
And of course whether it's worth paying £6000 - £12000 ukp to be rid of them.
regards
Raja
Looks like not too many realizes what`s the clue about speakerwires; keep the R low like in not existing. Keep the signal-halves separated to avoid interference and avoid any stranded conductor.
Speakerwires as well as passive filters must be designed to handle all the amps power without hesitating
Real sound begins at 9awg, solid off course 😎
Speakerwires as well as passive filters must be designed to handle all the amps power without hesitating
Real sound begins at 9awg, solid off course 😎
Yes, that is the implication.hermanv said:
While humans can hear within a very wide range of spl's, we are not simultaneously sensitive to the lowest and the highest spl's.. We range, automatically. That is why they want me to have a very quiet surrounding for 14 hours prior to my baseline hearing exam, so that the auto-mechanism has settled into the highest sensitivity.hermanv said:
hermanv said:
Let's calculate the total energy first.
E = 1/2 CV^2.
E = .5 * 100 e-12 * 100 = .5 * 10,000 * 10e-12
E = .5 * 10e4 * 10e-12
E = .5 *10e-8
E = 5 *10e-9
5 nanojoules. Total.
So no matter what happens, we have only 5 nanojoules with which to disturb the signal. The signal being 12 watts.
That is 9 orders of magnitude below the signal. And that is the total storage..if the capacitance changes 1%, you're talking 50 picojoules. While there are methods available to measure 5 nanojoules or 50 picojoules, if it is buried within a 12 joule per second environment, it may as well not exist.
So yes, the physics is real, but the resultant effect numbers are shall we say, rather a tad low.
Cheers, John
Your calculations are way off wrong John. Speakercables are all about resistance, and the dynamic gain or loss can be huge.
That's why a few of us kept banging on about keeping voltage drop within reasonable levels (assuming you don't want to use the wire as a convenient method of Eq of some nature or other, which is often the case with FR drivers).
First off , I have to say I skipped most of this , as I've read SO many speaker wire threads it is quite ridiculous.
I agree with most of this. However, when you split the wire "signal halves" , you dramatically increase inductance , which according to AC impedence calculations, is a larger contributor to the overall impedence of the cable than the series resistance.
Capacitance and inductance are far more of an impact on final AC impedance than the series resistance.
The lower in frequency you go, the more important the DC resistance of a cable becomes. The higher in frequency you go, the more important the AC *impedance* becomes.
No voodoo here. It's really all about what you like and what wires will give you that sound.
I have been a fan of solid 14ga twisted pair for years. I scoffed at the idea of using smaller wire. ABout 4 months ago i tried some 30ga. solid , silver plated teflon jacketed wire. It sounds GREAT.
I think alot of this is system/component dependant, and also listener preference.
I also think there is alot of snake oil going around.
Just my $0.02
....................................Blake
I agree with most of this. However, when you split the wire "signal halves" , you dramatically increase inductance , which according to AC impedence calculations, is a larger contributor to the overall impedence of the cable than the series resistance.
Capacitance and inductance are far more of an impact on final AC impedance than the series resistance.
The lower in frequency you go, the more important the DC resistance of a cable becomes. The higher in frequency you go, the more important the AC *impedance* becomes.
No voodoo here. It's really all about what you like and what wires will give you that sound.
I have been a fan of solid 14ga twisted pair for years. I scoffed at the idea of using smaller wire. ABout 4 months ago i tried some 30ga. solid , silver plated teflon jacketed wire. It sounds GREAT.
I think alot of this is system/component dependant, and also listener preference.
I also think there is alot of snake oil going around.
Just my $0.02
....................................Blake
Of course. Basically what I've been saying too.
I suspect Palerider was making the assumption that nothing funny was being pulled with the geometry either, & that the wire itself is not being deliberately used as a form of Eq.
I used 30ga magnet wire a few years ago for a pair of horns with a high DF to help optimise the interface. Better to use resistive wire in my book than a resistor itself. Wire is no different to anything else; you just have to know exactly what you're doing & why.
I suspect Palerider was making the assumption that nothing funny was being pulled with the geometry either, & that the wire itself is not being deliberately used as a form of Eq.
I used 30ga magnet wire a few years ago for a pair of horns with a high DF to help optimise the interface. Better to use resistive wire in my book than a resistor itself. Wire is no different to anything else; you just have to know exactly what you're doing & why.
Skin effect only matters at high freq. The math Ive seen shows it just starts to appear around 15khz. And is inaudible.
Put your money where your mouth is. Look up the PEAR cable challange (some debunker will give YOU a million dollars if you can hear the difference between $7k speaker wires and generic heavey gauge.) Let me know when your buying us all beer.
One more thing, mic out and mic pre in impedances are low, usaully 200 ohms each (matching for max power transfer) and low to reject external noise. The exception is mics with built in amps ( alot of them, all condensers)
Personal experience. Even multiple solid , individually shielded cables sound like they introduce a harshness to the treble, IMO. The CAT 5 DIY cables for example. Built some, no longer use them .
Ok. I couldn't tell you why. Although the skin effect doesn't come into play until 15k, perhaps it affects how the amp loads up ?
I'll look into that. Depending on the components used, you might NOT be able to hear a difference. If the output impedence is super low, it would be hard to hear a difference.
Are you saying you haven't heard a difference after switching cables ?
..............................Blake
http://gizmodo.com/gadgets/exclusiv...00-challenge-we-search-for-answers-315250.php
....................Blake
....................Blake
A couple of points here.
1) As speaker efficiency goes up (all other things being equal) so the more is revealed of components upstream from them. Especially if there's no XO anywhere near our critical hearing BW. That's partially why systems based around FR / WR drivers often need some minor tweaking to optimise their interface / load to the amplifer.
2) I doubt many people would suggest that all speaker cables sound the same (or perhaps I should say, contribute to the reproduction of the same sound). If anyone doesn't believe that, try comparing a 50ft run of 10ga to the same length of 24ga into a typical commercial speaker of modest efficiency / load & see how far you get. Challenges like the aforementioned are useful, but you have to compare like with like, especially WRT resistance.
Solid core nominally should be superior in terms of sheer efficiency -the big telephone companies did a fair bit of work on the subject, or farmed it out to 3rd party researchers -not surprising really, given their understandable wish to get the most from the least. Is is audible in hifi terms? Possibly. As a rule, I prefer to use it when I have the option. Bit more copper per gauge, no potential for corrosion between strands that don't exist etc.
1) As speaker efficiency goes up (all other things being equal) so the more is revealed of components upstream from them. Especially if there's no XO anywhere near our critical hearing BW. That's partially why systems based around FR / WR drivers often need some minor tweaking to optimise their interface / load to the amplifer.
2) I doubt many people would suggest that all speaker cables sound the same (or perhaps I should say, contribute to the reproduction of the same sound). If anyone doesn't believe that, try comparing a 50ft run of 10ga to the same length of 24ga into a typical commercial speaker of modest efficiency / load & see how far you get. Challenges like the aforementioned are useful, but you have to compare like with like, especially WRT resistance.
Solid core nominally should be superior in terms of sheer efficiency -the big telephone companies did a fair bit of work on the subject, or farmed it out to 3rd party researchers -not surprising really, given their understandable wish to get the most from the least. Is is audible in hifi terms? Possibly. As a rule, I prefer to use it when I have the option. Bit more copper per gauge, no potential for corrosion between strands that don't exist etc.
Nihilist said:
We went thru a lot of CAT 5 receipes and found that a pair of single solid core styrands had a decided edge with the speaker/amp combos most often found around here (single driver + small tube amp) ... and this falls cleanly into the frugal-phile(tm) camp given that antone who works anywhere near computers can usually get sufficient for nothing.
dave
I use the "pair of cat 5 single strands" kinda thing like dave mentioned for quite a while on everything (except subs).
Still use it with bananas on one end & alligator clips on the other for testing stuff.
Quick, cheap, easy, & a good known baseline.
Then I tried that "white lightning" ($7 garden center white outdoor extension cord) thing someone was raving about just to prove to myself that it couldn't make that much of a difference.
It did...
I played something, changed one side, and was going to sit down to listen to it, (listen to one side vs the other, then change both back and forth), and my wife called from the other room asking what I just changed to make the mids have more body... It really did make that much of a difference...
EL84 SET or PP to a FE166 or 108; same in any combination for my specific amps & speakers & room YMMV.
Maybe there is something to hi$ cables?
I heard a demo @ RMAF, where Roy, from Hi-Fi + played a system (with good cables), played the same CD in an otherwise identical system with matching cables (from the same company), and there was a very noticable improvement.
But the real kicker was changing those cables out for some with some kind of "anti-vibration" black boxes, that absorb vibration transmitted through the cable.
Sounds like "snake oil," but those were an amazing improvement over the other two.
I dunno...
Still use it with bananas on one end & alligator clips on the other for testing stuff.
Quick, cheap, easy, & a good known baseline.
Then I tried that "white lightning" ($7 garden center white outdoor extension cord) thing someone was raving about just to prove to myself that it couldn't make that much of a difference.
It did...
I played something, changed one side, and was going to sit down to listen to it, (listen to one side vs the other, then change both back and forth), and my wife called from the other room asking what I just changed to make the mids have more body... It really did make that much of a difference...
EL84 SET or PP to a FE166 or 108; same in any combination for my specific amps & speakers & room YMMV.
Maybe there is something to hi$ cables?
I heard a demo @ RMAF, where Roy, from Hi-Fi + played a system (with good cables), played the same CD in an otherwise identical system with matching cables (from the same company), and there was a very noticable improvement.
But the real kicker was changing those cables out for some with some kind of "anti-vibration" black boxes, that absorb vibration transmitted through the cable.
Sounds like "snake oil," but those were an amazing improvement over the other two.
I dunno...
Vibration transmitted through the wire? What sort? I assume, as they had little black boxes attached, that they were made by Transparent, and, that that you're refering to electrical resonance?
If so, irrespective of how decent the system sounded with those particular wires in place (I don't doubt your assertion that it did, although methinks this wasn't a double-blind test), it won't have had a whole lot to do with electrical resonance, because speaker wire does not resonate at audio frequencies. Not even ordinary zip cord. Anyone wo tells you otherwise are either liars, ignorant of basic electrical principles, or using a new form of physics hitherto unknown to human kind. 😉http://www.audioholics.com/education/cables/debunking-the-myth-of-speaker-cable-resonance
If so, irrespective of how decent the system sounded with those particular wires in place (I don't doubt your assertion that it did, although methinks this wasn't a double-blind test), it won't have had a whole lot to do with electrical resonance, because speaker wire does not resonate at audio frequencies. Not even ordinary zip cord. Anyone wo tells you otherwise are either liars, ignorant of basic electrical principles, or using a new form of physics hitherto unknown to human kind. 😉http://www.audioholics.com/education/cables/debunking-the-myth-of-speaker-cable-resonance
Hi Robert, were those "black boxes" by any chance "cable elevators" i.e., tiny lifters that lift the cables off the floor every 6 or 10 inches? Also, on your garden center $7 outdoor extension cord, may I ask was the wire inside solid vs. stranded, approximate gauge, copper?
EDIT: posted this before I saw Scott's message above. Still curious for details though!
EDIT: posted this before I saw Scott's message above. Still curious for details though!
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